Electrical power storage system using hydrogen and method for storing electrical power using hydrogen

ABSTRACT

In one embodiment, an electrical power storage system using hydrogen includes a power generation unit generating power using hydrogen and oxidant gas and an electrolysis unit electrolyzing steam. The electrical power storage system includes a hydrogen storage unit storing hydrogen generated by the electrolysis and supplying the hydrogen to the power generation unit during power generation, a high-temperature heat storage unit storing high temperature heat generated accompanying the power generation and supplying the heat to the electrolysis unit during the electrolysis, and a low-temperature heat storage unit storing low-temperature heat, which is exchanged in the high-temperature heat storage unit and generating with this heat the steam supplied to the electrolysis unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of Ser. No. 13/208,031 filed on Aug.11, 2011, now U.S. Pat. No. 8,394,543, which is a continuation of priorInternational Application No. PCT/JP2010/000905 filed on Feb. 15, 2010,which is based upon and claims the benefit of priority from JapanesePatent Applications No. 2009-032494 filed on Feb. 16, 2009, No.2009-051558 filed on Mar. 5, 2009, and No. 2010-026457 filed on Feb. 9,2010; the entire contents of all of which are incorporated herein byreference.

FIELD

Embodiments described herein relate generally to an electrical powerstorage system using hydrogen and a method for storing electrical powerusing hydrogen.

BACKGROUND

In the case where there is a large difference in power consumptionbetween the daytime and the nighttime or in the case of a power systemwith numerous interconnected wind power plants whose power generatingcapability varies depending on the wind condition, there is needed apower storage apparatus which stores surplus power in the nighttime orthe like and discharges electricity during the daytime when the powergoes short to correspond to a peak load, so as to effectively utilize apower generation facility. The most representative one is a pumpedstorage hydroelectric plant. In this plant, water is pumped to an upperdam during the nighttime to effectively store surplus power during thenighttime, and power is generated with a hydraulic turbine generatorusing the stored water in the daytime hours when a large power isconsumed, so as to correspond to the peak load during the daytime.

The pumped storage hydroelectric plant has good responsiveness as alarge power generation facility, and thus assumes the central role ofequalizing loads of power systems. However, the power storage technologyusing the pumped storage hydroelectric plant is limited in geographicalconditions such as whether it is possible to use a river or seawater,whether it is possible to build a dam, and so on. There is a furtherlimitation that it is not applicable unless the input/output capacity ofthe system is 200 MW at the minimum.

As a relatively large power storage facility other than the pumpedstorage hydroelectric plant, power storage apparatuses using hydrogenare known. It is known that a power storage apparatus which includeselectrolyzing and power generating means having a solid-oxideelectrolyte and combines a steam electrolysis cell and a fuel cell. Asolid electrolyte fuel cell can generate power by adding oxygen andhydrogen. Further, as backward reaction, it is also possible to applyvoltage to the added steam to electrolyze it for obtaining oxygen andhydrogen. Utilizing this principle, steam is electrolyzed by surpluspower to produce hydrogen, and the hydrogen is utilized to generatepower when power is needed.

A common heat storage technique is known. It is known that an apparatussuch that waste heat at 200° C. or lower is stored in a latent heatstorage material such as sodium acetate 3-hydrate or magnesium chloride6-hydrate, and heat is exchanged between the latent heat storagematerial and a heat medium for utilizing the waste heat. A heat storagetechnique applied to solar power generation is known, in which moltensalts corresponding to respective temperatures of 649° C. or higher,816° C. or higher, 927° C. or higher, and 982° C. or higher are used asa heat storage material. It is known that a heat storage unit in which amolten salt as a heat storage material is filled in a porous ceramiccontainer.

In power storage apparatuses using hydrogen, heat which is generatedmainly during power generation is utilized effectively, and it isimportant how to supply heat required for electrolysis. Heat obtainedmainly during power generation is used for air conditioning. However, inan air conditioner application, heat can be supplied only in thevicinity, and demands for air conditioning do not always match thegenerated heat amount. Thus, the heat cannot always be utilizedeffectively. It is known that heat generated during power generation isstored in a heat accumulator, and the stored heat is used for generatinghydrogen. Also in this case, it cannot be said that use efficiency ofheat generated during power generation is always high.

Incidentally, in a power storage apparatus or a heat storage apparatus,ceramic members are used which excel in heat resistance, strength,toughness, and so on. Further, ceramic members are used in variousapparatuses as a heat resistant member, abrasion resistant member, anabrasive, a precision machine member, and so on. In recent years,application mainly of nonoxide-based ceramic members of a siliconcarbide (SiC), a silicon nitride (Si₃N₄) and the like is in progress tosemiconductor manufacturing apparatus parts, parts for energy equipmentof nuclear energy or a gas turbine, space structural parts, automotiveparts such as engine parts and exhaust gas filters, heat exchangerparts, pump parts, mechanical sealing parts, bearing parts, slidingparts, and so on.

Ceramic members generally contract about 20% during sintering, and henceit is difficult to fabricate large parts and complicated shape partswith them. Accordingly, attempts have been made to prepare a pluralityof ceramic members and couple them together to produce a large part or acomplicated shape part. As a method to join ceramic members together,there has been proposed a method to join a plurality of ceramic membersby using reaction sintering of a silicon carbide.

It is known that a method to join a plurality of ceramic members formedof a silicon carbide-silicon composite sintered body or the like via asilicon carbide-silicon composite material layer (joining layer). Also,after a plurality of ceramic members are joined together with an organicresin-based adhesive, the joined part is impregnated with moltensilicon. The joining layer is formed of silicon carbide particles, whichare based on reaction between carbon in the organic resin and the moltensilicon, and a silicon phase existing in interstices among theparticles.

Further, after a plurality of ceramic members are joined with anadhesive containing a silicon carbide powder, a carbon powder, and anorganic resin, the joined part is impregnated with molten silicon. Inthis case, in addition to silicon carbide particles based on the siliconcarbide powder in the adhesive, the joining layer contains siliconcarbide particles based on reaction between carbon contents in thecarbon powder and the organic resin and the molten silicon, and thesilicon phase is made to exist in interstices among these siliconcarbide particles. In either case, a thermosetting resin is used as theorganic resin to be an adhering component and a viscous component in theadhesive.

By the joining method described above, a free silicon phase exists ininterstices among the silicon carbide particles forming the joininglayer (silicon carbide-silicon composite material layer), which improvesdenseness or mechanical properties of the joining layer. Thus, joiningstrength among a plurality of ceramic members can be enhanced. However,it is known that, since the adhesive use a thermosetting resin, it isnecessary to cure the thermosetting resin by heat treatment whenobtaining a shaped product made by preliminarily joining a plurality ofceramic members (a shaped product before being impregnated with moltensilicon). The thermosetting resin becomes soft once while being heated,and thus it is possible that a displacement or the like occurs in ajoined part of the shaped product, making it unable to keep its intendedshape.

Therefore, so as to keep the shape of a preliminarily shaped product or,in particular, the shape of a joined part by using an adhesive duringcuring treatment for the thermosetting resin, it is necessary to fix thepreliminary shaped product with a jig. The jig to fix the preliminaryshaped product needs to be prepared corresponding to the shapes andsizes of various types of parts, and thus becomes a main cause toincrease manufacturing costs and the number of manufacturing processesof ceramic composite members such as joined members. Further, even whenthe preliminary shaped product is fixed with a jig, the thickness of thejoined part may be uncontrollable, and dispersion in thickness of thefinal joining part may occur, which decreases material propertiesincluding joining strength.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram schematically illustrating an electrical powerstorage system using hydrogen according to a first embodiment.

FIG. 2 is a perspective view illustrating an example of ahigh-temperature heat storage device in the electrical power storagesystem of the first embodiment.

FIG. 3 is cross-sectional views illustrating a first structural exampleof a capsule used in the high-temperature heat storage deviceillustrated in FIG. 2, where FIG. 3A is a cross-sectional viewillustrating a state before a first ceramic member and a second ceramicmember are joined, and FIG. 3B is a cross-sectional view illustrating astate that the first ceramic member and the second ceramic member arejoined.

FIG. 4 is a cross-sectional view illustrating a second structuralexample of a capsule used in the high-temperature heat storage deviceillustrated in FIG. 2.

FIG. 5 is a cross-sectional view illustrating a third structural exampleof a capsule used in the high-temperature heat storage deviceillustrated in FIG. 2.

FIG. 6 is a block diagram schematically illustrating an electrical powerstorage system using hydrogen according to a second embodiment.

FIG. 7 is a block diagram schematically illustrating an electrical powerstorage system using hydrogen a third embodiment.

FIG. 8 is a block diagram schematically illustrating an electrical powerstorage system using hydrogen according to a fourth embodiment.

FIG. 9 is a cross-sectional view illustrating manufacturing processes ofa ceramic joined member (ceramic composite member) according to anembodiment, where FIG. 9A is a cross-sectional view illustrating a statethat the first ceramic body and a second ceramic body are joined with aviscous material, FIG. 9B is a cross-sectional view illustrating a statethat the viscous material is made to be a porous body, and FIG. 9C is across-sectional view illustrating a state that the first ceramic bodyand the second ceramic body are joined by impregnating the porous bodywith molten silicon.

DETAILED DESCRIPTION

According to one embodiment, there is provided an electrical powerstorage system using hydrogen including a power generation unitgenerating power using hydrogen and oxidant gas, an electrolysis unitelectrolyzing steam to generate hydrogen, a hydrogen storage unitstoring hydrogen generated by the electrolysis and supplying thehydrogen to the power generation unit during power generation, ahigh-temperature heat storage unit storing first heat generatedaccompanying the power generation and supplying the first heat to theelectrolysis unit during the electrolysis, and a low-temperature heatstorage unit storing second heat, which is exchanged in thehigh-temperature heat storage unit and is lower than the temperature ofthe first heat stored in the high-temperature heat storage unit, andgenerating with the second heat the steam supplied to the electrolysisunit.

According to another embodiment, there is provided a ceramic joiningmaterial including a mixture containing a silicon carbide powder havinga mean particle diameter in the range of 0.5 μm to 5 μm, a carbon powderhaving a mean particle diameter in the range of 0.3 μm to 3 μm and aroom temperature setting resin having viscosity and adhesiveness, and acuring agent of the room temperature setting resin which cures themixture, in which the volume ratio of the silicon carbide powder to allthe powder components in the joining material is in the range of 18% to60%.

Embodiments will be described with reference to the drawings. Note thatthe same or similar components are denoted by common numerals, andduplicated descriptions are omitted.

To begin with, a first embodiment of an electrical power storage systemwill be described. FIG. 1 is a block diagram schematically describingthe structure of the electrical power storage system using hydrogenaccording to the first embodiment. The electrical power storage system(apparatus) 10 illustrated in FIG. 1 includes a power/hydrogenconverting device 11. The power/hydrogen converting device 11 is anapparatus capable of performing power generation and electrolysis ofsteam (generation of hydrogen) while switching these operations overtime. Specifically, it is formed of a solid electrolyte fuel cell havinga solid-oxide electrolyte.

The solid electrolyte fuel cell combines a power generation unitgenerating power using hydrogen and oxidant gas, and an electrolysisunit electrolyzing steam. In FIG. 1, directions of flows of electricity(power), air (oxygen), hydrogen, heat in a power generation operatingmode are denoted by black arrows, and directions of flows of electricity(power), steam, heat, hydrogen in an electrolysis operating mode aredenoted by white arrows.

In the power generation operating mode, hydrogen is supplied to ahydrogen electrode (fuel electrode) of the power/hydrogen convertingdevice (solid electrolyte fuel cell) 11, and oxidant gas (oxygen or aircontaining oxygen) is supplied to an oxidant electrode, therebyperforming power generation. On the other hand, in the electrolysis(hydrogen generation) operating mode, steam is supplied to the hydrogenelectrode side of the power/hydrogen converting device (solidelectrolyte fuel cell) 11 and power is supplied simultaneously, therebyelectrolyzing the steam to generate hydrogen.

The electrical power storage system 10 includes a hydrogen storage unit12 storing hydrogen which is generated during the electrolysis (hydrogengeneration) operating mode. As the hydrogen storage unit 12, forexample, a hydrogen storage tank is used. The hydrogen stored in thehydrogen storage unit 12 is supplied to the hydrogen electrode (fuelelectrode) of the power/hydrogen converting device (solid electrolytefuel cell) 11 during the power generation operating mode.

The electrical power storage system 10 further includes ahigh-temperature heat storage unit 13 storing high temperature heat of650° C. to 1000° C. generated in the power/hydrogen converting device 11during the power generation operating mode. The high temperature heatstored in the high-temperature heat storage unit 13 is supplied to thepower/hydrogen converting device 11 during the electrolysis operatingmode. Since steam electrolysis is heat absorbing reaction, it isnecessary to supply heat externally. Note that the electrical powerstorage system 10 includes, although omitted from illustration here, alow-temperature heat storage unit in addition to the high-temperatureheat storage unit 13. Details of the high-temperature heat storage unitand the low-temperature heat storage unit will be described later.

In the electrical power storage system 10, generally, for example, steamelectrolysis operation using power is performed during the nighttimewhen power demands are low and hydrogen is stored in the hydrogenstorage unit 12. During the daytime when power demands are high, thehydrogen stored in the hydrogen storage unit 12 is used for performing apower generating operation. Heat generated during the power generatingoperation is stored in the high-temperature heat storage unit 13 throughdischarged steam or a heat medium which exchanged heat with thedischarged steam. In the high-temperature heat storage unit 13, forexample, heat of 650° C. to 1000° C. is stored.

During the electrolysis operation, water (steam) is supplied to thehydrogen electrode side of the power/hydrogen converting device (solidelectrolyte fuel cell) 11. At this time, heat needed for theelectrolysis operation is discharged from the high-temperature heatstorage unit 13 via the steam or the heat medium. The temperature of thesteam or heat medium discharging heat is 600° C. to 1000° C., forexample. Hydrogen is generated and discharged by electrolysis of steamon the hydrogen electrode side, and this hydrogen is stored in thehydrogen storage unit 12. Concurrently, oxygen is generated anddischarged on the oxygen electrode side.

A specific structural example of the high-temperature heat storage unit13 will be described with reference to FIG. 2. FIG. 2 is a perspectiveview illustrating an example of a heat storage device forming thehigh-temperature heat storage unit 13 of the electrical power storagesystem 10 of the first embodiment. The high-temperature heat storageunit (heat storage device) 13 includes a plurality of capsules 14 inwhich a heat storage material is encapsulated, and a heat storagecontainer 15 housing these capsules 14. The heat storage container 15forms flow paths for a heat medium fluid flowing around the capsules 14.

The capsules 14 are cylindrical containers for example, in which a heatstorage material (not illustrated) is encapsulated. The heat storagematerial used for the high-temperature heat storage unit 13 is onehaving a melting point to melt when storing heat and solidify whenreleasing heat, and it is preferred to have, for example, a meltingpoint in the temperature range of 650° C. to 1000° C. with heat ofsolution of 200 kJ/kg or higher and specific heat of solid and liquid of1 kJ/kg·K or higher. It is preferred that the capsules 14 have corrosiveresistance to the encapsulated heat storage material and conductivity ofheat of 650° C. to 1000° C. at 10 W/m·K or higher.

During the power generating operation, steam at a high temperature of650° C. to 1000° C. for example obtained by the heat generated in thepower/hydrogen converting device 11 or the heat medium fluid whichexchanged heat with this steam is introduced into the heat storagecontainer 15 and flows outside the capsules 14. Thus, the capsules 14and the heat storage material in a solid state encapsulated therein areheated. The heat storage material is heated and melted, and changes fromsolid to liquid. By utilizing latent heat during this phase transitionfrom solid to liquid, a large amount of heat can be stored in arelatively small amount of heat storage material.

During the electrolysis operation, the high temperature heat generatedwhen the heat storage material in a liquid state solidifies istransferred to the heat medium fluid via the capsules 14. By sendingthis high-temperature heat medium fluid to the power/hydrogen convertingdevice 11, necessary heat can be supplied during the electrolysisoperation. In this case, the heat medium fluid such as steam is not indirect contact with a molten salt or the like as the heat storagematerial and passes through the flow paths outside the capsules 14.

As the heat storage material used for the high-temperature heat storageunit 13, at least one selected from sodium chloride (NaCl), potassiumchloride (KCl), magnesium chloride (MgCl₂), calcium chloride (CaCl₂),lithium fluoride (LiF), sodium fluoride (NaF), lithium carbonate(Li₂CO₃), sodium carbonate (Na₂CO₃), potassium carbonate (K₂CO₃), andlithium hydroxide (LiH) is exemplified. These may also be used in amixture.

Depending on the type of the solid electrolyte of the power/hydrogenconverting device (solid electrolyte fuel cell) 11 or on operatingconditions, the temperature of the heat discharged during powergeneration differs. Thus, it is preferred that the type of the heatstorage material be selected depending on the temperature of dischargedheat and a heat storage capacity. By using a single one of theabove-described chemical compounds (molten salts), it is possible tosuppress variation in heat storage/discharge characteristics, whichbecomes a problem in relation with varying temperatures and enlargementof apparatus. Thus, stability of the electrical power storage system 10can be improved.

It is preferred that the capsules 14 be formed of at least one ceramicmember selected from a silicon carbide (SiC) sintered body, a siliconcarbide-silicon (SiC—Si) composite sintered body, a siliconcarbide-based long fiber (SiC-long fiber (SiC long fiber or the like))composite material, a boron carbide (B₄C) sintered body, a siliconnitride (Si₃N₄) sintered body, a boron nitride (BN) sintered body, andgraphite (C). With the capsules 14 formed of a ceramic member, heattransfer between the heat storage material and the steam or heat mediumfluid can be improved, and weight reduction and size reduction of theheat storage device as well as improvement in overall efficiency can beachieved.

The capsules 14 are formed of a first and a second ceramic member, atleast one of which has a container shape. A specific example of theceramic members is as described above. FIG. 3 illustrates a firststructural example of the capsules 14. The capsule 14 illustrated inFIG. 3 has a first ceramic member 16 having a container shape and asecond ceramic member 17 having a lid shape. In addition, both the firstceramic member 16 and the second ceramic member 17 may have a containershape. For encapsulating the heat storage material in such a capsule 14,there is a method as follows.

First, as illustrated in FIG. 3A, on an opening of the first ceramicmember 16 in which the heat storage material (not illustrated) ishoused, the second ceramic member 17 is disposed via a joining material18. As the joining material 18, a ceramic precursor, a carbon adhesive,a silicon brazing material, or the like is used. It is possible to applya silicon carbide-silicon composite body or the like to join the firstceramic member 16 and the second ceramic member 17. Next, as illustratedin FIG. 3B, heat treatment at temperatures corresponding to the joiningmaterial 18 is performed, thereby joining the first ceramic member 16and the second ceramic member 17 via a joining layer 19.

As the ceramic precursor, a polycarbosilane, a polycarbosilazane, apolysilazane, a polyborosiloxane, a polymetaloxane, or the like is used.After firing, these precursors generate a ceramic layer formed of aSi—C-based ceramic, a Si—C—N-based ceramic, a Si—O-based ceramic, aSi—B—C-based ceramic, or the like as the joining layer 19. The carbonadhesive contains a graphite powder and a resin or the like, and afterfiring, a carbon layer is generated as the joining layer 19. As thesilicon brazing material, a foil, a paste, or the like is used, andafter firing (after brazing), these materials form a silicon layer asthe joining layer 19.

A joining method applying a silicon carbide-silicon composite body issuch that an adhesive containing carbon components such as a carbonadhesive or an organic resin-based adhesive is used as the joiningmaterial 18 to join the first ceramic member 16 and the second ceramicmember 17, and thereafter heat treatment is performed with silicon (Si)being present to form the joining layer 19 formed of a siliconcarbide-silicon composite body, thereby joining the first ceramic member16 and the second ceramic member 17. The silicon is supplied by, forexample, impregnating the joining layer (joining material 18) withmolten silicon. At this moment, a part of the molten silicon is activelyleft, so as to form the joining layer 19 of a silicon carbide-siliconcomposite body.

The heat storage material is encapsulated in the capsule 14 formed byjoining the first ceramic member 16 and the second ceramic member 17.When the heat storage material is encapsulated in the capsule 14, ifjoining with high density and strength is not made, there arises aproblem such as a leak of the heat storage material from the joiningpart. Further, when there is a difference in thermal physical propertybetween the ceramic members 16, 17 combining a heat transfer tube andthe joining part, damage or the like originating in the joining partoccurs easily due to a thermal cycle while storing/discharging heat. Thejoining layers 19 described above are all dense and strong, and also hasexcellent thermal physical properties. Thus, it is possible to prevent aleak of the heat storage material from the joining part, damage or thelike originating in the joining part, and the like. Therefore, a heatstorage device having stable heat storage/discharge characteristics canbe obtained.

It is preferred to apply a silicon carbide-silicon composite body forthe joining layer 19 between the first ceramic member 16 and the secondceramic member 17. It is preferred that the silicon carbide-siliconcomposite body forming the joining layer 19 have a structure havingsilicon carbide particles and a silicon phase which exists continuouslyin a network form in interstices among the silicon carbide particles.Such a silicon carbide-silicon composite body can be formed byimpregnating a porous body having first silicon carbide particles andcarbon with molten silicon, causing the carbon in the porous body toreact with the molten silicon to generate second silicon carbideparticles, and leaving part of the molten silicon as the silicon phase.

The porous body having the first silicon carbide particles and carbon isformed as follows for example. First, as the joining material 18, thereis prepared a viscous material containing a silicon carbide powder to bethe first silicon carbide particles, a carbon powder, and a roomtemperature setting resin and a curing agent thereof (joining material).It is preferred that the silicon carbide powder have a mean particlediameter in the range of 0.5 μm to 5 μm. It is preferred that the carbonpowder have a mean particle diameter in the range of 0.3 μm to 3 μm.Further, it is preferred that the volume ratio of the silicon carbidepowder to all the powder components in the viscous material be in therange of 18% to 60%, and that the total mass ratio of the siliconcarbide powder and the carbon powder be in the range of 29% to 55% ofthe entire viscous material. Reasons for the limitations in thesenumbers will be described later.

Next, on the opening of the first ceramic member 16 in which the heatstorage material (not illustrated) is housed, the second ceramic member17 is disposed via the joining material 18 formed of the above-describedviscous material. A silicon foil or the like can be used as a supplysource of the molten silicon. When the viscous material is applied on ajoining face of the second ceramic member 17, the silicon foil isdisposed on a joining face of the first ceramic member 16 in a manner tocontact the viscous material. Alternatively, when the viscous materialis disposed between the first ceramic member 16 and the second ceramicmember 17, the silicon foil may be disposed around them in a manner ofwrapping them. When the viscous material and the silicon foil are incontact, the molten silicon can be supplied sufficiently into the porousbody during heat treatment.

Next, the room temperature setting resin in the viscous material iscured under room temperature and becomes a solidified body. This resultsin preliminary joining of the first ceramic member 16 and the secondceramic member 17, and thus spilling of the heat storage material or thelike can be prevented while being transferred to a heat treatmentfurnace or handled. Subsequently, by performing heat treatment to thesolidified body of the viscous material, a cured product of the roomtemperature setting resin is carbonized. This causes the solidified bodyof the viscous material to be porous. Then, the joining layer 19 formedof the silicon carbide-silicon composite body is formed by impregnatingsuch a porous body with molten silicon, causing the carbon in the porousbody to react with the molten silicon to generate second silicon carbideparticles, and leaving part of the molten silicon as the silicon phase.Note that details of conditions for forming the joining layer 19 formedof the silicon carbide-silicon composite body will be described later.

The shapes of the first and second ceramic members 16, 17 forming thecapsules 14 are not limited to the shape illustrated in FIG. 3. It isalso effective to make the shapes of the joining faces of the firstceramic member 16 having a container shape and the second ceramic member17 having a lid shape to be engaging shapes as illustrated in FIG. 4 andFIG. 5. FIG. 4 and FIG. 5 illustrate joining faces such that projectionsare provided on the joining face of the second ceramic member 17, andrecesses corresponding to the projections are provided on the joiningface of the first ceramic member 16. With such shapes of the joiningfaces, a leak or the like of the heat storage material encapsulated inthe capsules 14 can be prevented more securely.

Regarding renewable energy such as solar energy and wind power in aregion where the weather changes largely, employing an electrical powerstorage system having a solid electrolyte fuel cell which performs powergeneration and steam electrolysis is effective for improving powerstorage efficiency. Also regarding renewable energy such as solar energyin a region where there is less variation in nighttime power andweather, employing an electrical power storage system having a solidelectrolyte fuel cell which performs power generation and steamelectrolysis is effective for improving power storage efficiency. Theelectrical power storage system 10 of this embodiment stores heat of650° C. to 1000° C. discharged during power generation and uses thisheat during electrolysis of steam, and thus the stored heat can beutilized effectively. Therefore, the overall efficiency of theelectrical power storage system can be increased largely.

Next, a second embodiment of an electrical power storage system usinghydrogen will be described. FIG. 6 is a block diagram schematicallyillustrating the structure of the electrical power storage systemaccording to the second embodiment. The electrical power storage system20 illustrated in FIG. 6 includes a power generation unit 21 whichgenerates power using hydrogen and oxidant gas, and an electrolysis unit22 which electrolyzes steam. For the power generation unit 21, forexample, a solid electrolyte fuel cell having a solid-oxide electrolyteis employed. For the electrolysis unit 22, a steam electrolysis cellincluding a solid-oxide electrolyte is employed. The steam electrolysiscell forming the electrolysis unit 22 is a device which is separate fromthe solid electrolyte fuel cell forming the power generation unit 21.

In the second embodiment, the part corresponding to the power/hydrogenconverting device 11 in the first embodiment is separated into the fuelcell which performs power generation (power generation unit 21) and thesteam electrolysis cell which electrolyzes steam (electrolysis unit 22),which are formed of separated devices respectively. The other structureis the same as that of the first embodiment. In the second embodiment,switching of operating mode between power generation and steamelectrolysis as in the first embodiment is unnecessary, thereby allowingto perform more flexible power generation and steam electrolysis.Accordingly, it is possible to more flexibly correspond to variation inpower demand or the like, which contributes to stable supply of power.Moreover, similarly to the first embodiment, the overall efficiency ofthe electrical power storage system which effectively utilizes heat canbe improved.

Next, a third embodiment of an electrical power storage system usinghydrogen will be described. FIG. 7 is a block diagram schematicallyillustrating the structure of the electrical power storage systemaccording to the third embodiment. The third embodiment illustrates anelectrical power storage system 30 including a high-temperature heatstorage unit 13 and a low-temperature heat storage unit 31. Theelectrical power storage system 30 of the third embodiment includes thelow-temperature heat storage unit 31 in addition to the high-temperatureheat storage unit 13 of the first embodiment.

In the electrical power storage system 30 of the third embodiment, heatgenerated in the power/hydrogen converting device 11 during powergeneration is stored in the high-temperature heat storage unit 13 viasteam or a heat medium which exchanged heat with this steam. In thehigh-temperature heat storage unit 13, heat of 650° C. to 1000° C. isstored. Further, heat of 100° C. to 600° C. after being exchanged in thehigh-temperature heat storage unit 13 is stored in the electrical powerstorage system 30 via steam or a heat medium which exchanged heat withthis steam.

During electrolysis of steam, steam is generated by evaporating waterwith heat discharged from the low-temperature heat storage unit 31, andthis steam is supplied to the hydrogen electrode side of thepower/hydrogen converting device 11. Moreover, heat needed duringelectrolysis of steam is supplied by discharging from thehigh-temperature heat storage unit 13 via steam or a heat medium. Thetemperature of the steam or heat medium discharging heat is 600° C. to900° C., for example. Hydrogen is generated and discharged byelectrolysis of steam on the hydrogen electrode side of thepower/hydrogen converting device 11, and this hydrogen is stored in thehydrogen storage unit 12. Concurrently, oxygen is generated anddischarged on the oxygen electrode side.

For the low-temperature heat storage unit 31, a heat storage devicehaving a structure similar to that of the high-temperature heat storageunit 13 illustrated in FIG. 2 is employed. As the heat storage materialused for the low-temperature heat storage unit 31, it is preferred touse an organic matter or a molten salt having a melting point in atemperature range of 100° C. to 200° C., with heat of solution of 150kJ/kg or higher, and specific heat of solid and liquid of 1 kJ/kg·K orhigher. Examples of the organic matter forming such a heat storagematerial include xylitol, erythritol, mannitol, sorbitol, alditol, urea,and the like. Examples of the molten salt include aluminum chloride(AlCl₃), iron chloride (FeCl₃), lithium hydroxide (LiOH), sodiumhydroxide (NaOH), potassium hydroxide (KOH), sodium nitrite (NaNO₂),lithium nitrate (LiNO₃), sodium nitrate (NaNO₃), potassium nitrate(KNO₃), and the like.

Next, a fourth embodiment of an electrical power storage system usinghydrogen will be described. FIG. 8 is a block diagram schematicallyillustrating the structure of the electrical power storage systemaccording to the fourth embodiment. The electrical power storage system40 of the fourth embodiment includes, similarly to the secondembodiment, a power generation unit (solid electrolyte fuel cellincluding a solid-oxide electrolyte) 21 and an electrolysis unit (steamelectrolysis cell including a solid-oxide electrolyte) 22 which isseparate from the power generation unit. The other structure is the sameas that of the third embodiment.

The electrical power storage system 40 of the fourth embodiment hascharacteristics of both the second embodiment and the third embodiment.In the fourth embodiment, switching of operating mode between powergeneration and electrolysis as in the third embodiment is unnecessary,thereby allowing to perform more flexible power generation andelectrolysis. Accordingly, it is possible to more flexibly correspond tovariation in power demand or the like, which contributes to stablesupply of power. Moreover, since the low-temperature heat storage unit31 is provided in addition to the high-temperature heat storage unit 13similarly to the third embodiment, the overall efficiency of theelectrical power storage system which effectively utilizes heat improvesfurther.

The above-described embodiments exemplify the electrical power storagesystem of the present invention, and the present invention is notlimited thereto. For example, the structure of the low-temperature heatstorage unit 31 in the third and fourth embodiments may be one notsimilar to the high-temperature heat storage unit 13 illustrated in FIG.2. Extensions or modifications can be made within the range of thetechnical idea of the present invention, for example the structure of alatent heat storage device can be applied to the low-temperature heatstorage unit 31, and such extended or modified embodiments are includedin the technical scope of the present invention.

Next, an embodiment of a ceramic joining material and a manufacturingmethod of a ceramic composite member using the ceramic joining materialwill be described. The manufacturing method of a ceramic compositemember (joining method of ceramic members) according to this embodimentis applied to a forming method of the capsules 14 (joining method of thefirst ceramic member 16 and the second ceramic member 17) in theabove-described embodiments of the electrical power storage system, andspecifies specific conditions and the like in this application. However,the ceramic joining material and the manufacturing method of the ceramiccomposite member of this embodiment are not limited thereto and areapplicable to joining or repair of various ceramic bodies.

The ceramic joining material of this embodiment includes a firstcomponent formed of a mixture containing a silicon carbide powder, acarbon powder, and a room temperature setting resin, and a secondcomponent formed of a curing agent which cures the first component(mixture) (curing agent which cures the room temperature setting resin).The ceramic joining material as a viscous material prepared by mixingthe first component and the second component is used for joining orrepair of ceramic bodies. That is, as a mixture (viscous material) ofthe first component and the second component, the ceramic joiningmaterial is used for manufacturing a ceramic joined member formed byjoining a plurality of ceramic bodies or a ceramic composite member suchas a ceramic repaired member in which a part of a ceramic body isrepaired.

Examples of the ceramic bodies for which the ceramic joining material isapplied for joining or repair include molded bodies or sintered bodiesof silicide ceramics such as silicon carbides, silicon nitrides, andcomplex chemical compounds mainly containing them. Further, the materialis also applicable to ceramics other than the silicide ceramics and iseffective for carbide ceramics such as boron carbides and graphite.Specific examples of ceramic bodies include a silicon carbide-carboncomposite molded body, a silicon carbide-silicon composite sinteredbody, a silicon carbide sintered body, a silicon nitride sintered body,and graphite. The ceramic joining material is particularly effective forsilicon carbide-based ceramic bodies.

The ceramic joining material of this embodiment forms a silicon carbide(SiC)-silicon (Si) composite body through a shaping process, a heattreatment process, an impregnation process of molten silicon, and so on,which will be described later. The SiC—Si composite body includes firstSiC particles based on the silicon carbide powder in the joiningmaterial, second SiC particles generated by reaction between the carboncomponents (porous carbon generated by performing heat treatment(carbonization treatment) on a carbon powder and a cured product of aroom temperature setting resin) in the joining material and the moltensilicon, and a Si (free Si phase) filling interstices among the firstand second SiC particles. Such a SiC—Si composite body forms a joiningpart which joins a plurality of silicon-based ceramic bodies or a repairpart for repairing a part of a silicon-based ceramic body.

The first component of the ceramic joining material is formed of amixture containing a room temperature setting resin as a component toadd adhesiveness and viscosity, and the second component is formed of acuring agent which cures the first component (mixture). The roomtemperature setting resin and the curing agent form a room temperaturesetting resin composition, for which an epoxy-based resin composition ora phenol-based resin composition having a room temperature settingproperty is used. The room temperature setting resin composition isseparated into two components of a base resin, whose main component isthe room temperature setting resin, and a curing agent, which are mixedto be used just before working with it. In the ceramic joining material,for example, a silicon carbide powder, a carbon powder, and the baseresin of the room temperature setting resin composition are mixed (firstcomponent) in advance, and then the curing agent (second component) isblended therewith to be used for joining or repairing ceramic bodies.

In the room temperature setting epoxy-based resin composition, the baseresin contains, as a main component of the epoxy-based resincomposition, an epoxy resin of bisphenol-A type, bisphenol-F type,cresol-novolac type, phenol-novolac type, high polymer type, epoxypolyol, or the like. In addition to the epoxy resin, the base resingenerally contains an inorganic filler of silica, alumina, talc, clay,mica, quartz powder, titanium oxide, calcium carbonate, or the like. Inaddition, the silicon carbide powder and the carbon powder in the firstcomponent correspond to part of the inorganic filler in the resincomposition. Further, the base resin may contain various fillers andadditives, such as a hardening accelerator, a coloring agent, a couplingagent, and the like which are normally added to an epoxy-based resincomposition, as well as a solvent or the like for dilution. Therefore,the first component of the joining material may contain fillers andadditives, such as an inorganic filler, a hardening accelerator, acoloring agent, a coupling agent, and the like as well as a solvent orthe like for dilution, in addition to the room temperature setting epoxyresin.

Examples of the curing agent in the room temperature setting epoxy-basedresin composition include an acid anhydride, a polyamine, a polyamide, anovolac resin, an epichlorohydrin, and the like. The amount of thecuring agent (amount with respect to the epoxy resin in the base resin)is set appropriately according to its type and hardening reactionmechanism under room temperature, and further a hardening degree of theviscous material under room temperature, and so on. Such a curing agentof the room temperature setting epoxy resin is used as the secondcomponent of the joining material.

In the room temperature setting phenol-based resin composition, the baseresin contains, as a main component of the phenol-based resincomposition, a phenol resin such as a novolac, a resole, or the like. Inaddition to the phenol resin, the base resin generally contains aninorganic filler of silica, alumina, talc, clay, mica, quartz powder,titanium oxide, calcium carbonate, or the like. Further, the base resinmay contain various fillers and additives, such as a hardeningaccelerator, a coloring agent, a coupling agent, and the like which arenormally added to a phenol-based resin composition, as well as a solventor the like for dilution. Therefore, the first component of the joiningmaterial may contain fillers and additives, such as an inorganic filler,a hardening accelerator, a coloring agent, a coupling agent, and thelike as well as a solvent or the like for dilution, in addition to theroom temperature setting phenol resin.

Examples of the curing agent in the room temperature settingphenol-based resin composition include an acid anhydride, a polyamine, apolyamide, and the like. The amount of the curing agent (amount withrespect to the phenol resin in the base resin) is set appropriatelyaccording to its type and hardening reaction mechanism under roomtemperature, and further a hardening degree of the viscous materialunder room temperature, and so on. Such a curing agent of the roomtemperature setting phenol resin is used as the second component of thejoining material.

The ceramic joining material of this embodiment is such that a siliconcarbide powder and a carbon powder are mixed with the base resin of theroom temperature setting resin composition (first component), and acuring agent (second component) is mixed with this mixture to prepare aviscous material (mixture of the first component and the secondcomponent) to be used. The ceramic joining material has a resincomponent formed of a room temperature setting resin (fluid resincomponent such as a liquid resin component), and a powder componentbased on the silicon carbide powder and the carbon powder. The powdercomponent in the ceramic joining material means the silicon carbidepowder and the carbon powder, and does not include a powder componentblended in advance in the room temperature setting resin.

The silicon carbide powder blended in the first component of the ceramicjoining material has a mean particle diameter in the range of 0.5 μm to5 μm. When the mean particle diameter of the silicon carbide powder issmaller than 0.5 μm, a distribution state of respective components(carbon contents based on the silicon carbide powder, the carbon powder,and the resin) in a porous body formed by heat treating the mixture(viscous material) of the first component and the second component and adistribution state of components (the second SiC particles and the Siphase) in the SiC—Si composite body formed by impregnating the porousbody with molten Si become non-uniform. On the other hand, when the meanparticle diameter of the silicon carbide powder is larger than 5 μm, thesize of the Si phase tends to be too large. In either case, it is notpossible to increase the strength of the SiC—Si composite body.

The carbon powder has a mean particle diameter in the range of 0.3 μm to3 μm. When the mean particle diameter of the carbon powder is smallerthan 0.3 μm, flocculation occurs easily, and the distribution state ofthe second SiC particles and the Si phase in the SiC—Si composite bodybecomes non-uniform. When the mean particle diameter of the carbonpowder is larger than 3 μm, a chalking phenomenon occurs easily, and thestrength of the SiC—Si composite body decreases. Here, the chalkingphenomenon is such that a dense SiC layer is formed on a surface sidedue to volume increase during generation of SiC by reaction with moltensilicon, and permeation of the molten silicon to the inside is hindered,resulting in that the carbon inside remains unchanged. Further, when themean particle diameter of the carbon powder is too large, the meandiameter of the Si phase tends to be large, leading to decrease ordispersion in strength of the SiC—Si composite body forming the joiningpart or the repair part.

It is preferred that the ceramic joining material contain the siliconcarbide powder in the range of 18 volume % to 60 volume % with respectto the total powder component. When the volume ratio of the siliconcarbide powder is lower than 18 volume %, the first SiC particles whichfunctions as aggregate in the SiC—Si composite body become insufficient,and the distribution state of the second SiC particles and the Si phasecan easily become non-uniform. On the other hand, when the volume ratioof the silicon carbide powder is higher than 60 volume %, the Si phasein the SiC—Si composite body becomes too large. In either case, there isa concern that the strength of the SiC—Si composite body cannot beexhibited sufficiently. It is preferred that the volume ratio of thesilicon carbide powder to the total powder component be in the range of22% to 56%.

It is preferred that the total content of the silicon carbide powder andthe carbon powder in the ceramic joining material be in the range of 29mass % to 55 mass % of the entire material. By applying such a contentof the powder component (the silicon carbide powder and the carbonpowder), when the joining part joining a plurality of ceramic bodies orthe repair part for repairing a part of a ceramic body are formed, it ispossible to obtain a viscous material (the mixture of the firstcomponent and the second component of the ceramic joining material) bywhich joining parts or repair parts of various shapes and sizes can beeasily shaped. That is, formability (workability) of the joining partand the repair part with the ceramic joining material can be increased.

When the total content of the powder component formed of the siliconcarbide powder and the carbon powder is higher than 55 mass %, themixture (viscous material) of the first component and the secondcomponent of the ceramic joining material tends to be too high. Further,when the total content of the powder component is less than 29 mass %,conversely there is a concern that the viscosity of the mixture (viscousmaterial) of the first component and the second component becomes toolow. In either case, workability (formability) of the mixture (viscousmaterial) of the first component and the second component decreases. Itis more preferred that the total content of the silicon carbide powderand the carbon powder in the ceramic joining material be in the range of29 mass % to 40 mass %.

Further, when ceramic bodies to be joined or repaired are a densematerial like a sintered body, it is preferred to use the ceramicjoining material with a relatively large content of the powder component(joining material whose content of the powder component is on the 55mass % side). Conversely, when the ceramic bodies are porous like amolded body such as a green compact or the like, it is preferred to usethe ceramic joining material with a relatively small content of thepowder component (joining material whose content of the powder componentis on the 29 mass side).

When the powder component amount of the ceramic joining material isrelatively large (the content of the powder component is on the 55 mass% side), the shape retention of the mixture (viscous material) of thefirst component and the second component becomes high, and it is easy tobe joined to a ceramic body. However, when the ceramic bodies are porouslike a green compact, a resin component (liquid component) is absorbedinto the ceramic bodies, and thus, for example, the ceramic bodiesbecome difficult to be joined together. In such a case, it is preferredto use the ceramic joining material with a relatively small powdercomponent amount (the joining material whose content of the powdercomponent is on the 29 mass % side). With such a joining material, themixture (viscous material) of the first component and the secondcomponent cut into recess portions on the surface of a green compact,thereby improving the adhesiveness.

Regarding the ceramic joining material of this embodiment, the viscousmaterial prepared by mixing the first component and the second componentis given moderate viscosity based on the fluidity (liquidity or thelike) which the room temperature setting resin has, the blending amountof the powder component, and the like, and thus it can be shaped easilyon a joining face or a repair face of a ceramic body. Further, since theviscous material formed of the mixture of the first component and thesecond component hardens under room temperature, a predetermined shaperequired for the joining part or the repair part can be maintainedeasily. Therefore, by using the ceramic joining material of thisembodiment, it is possible to easily and precisely form the joining partor the repair part on ceramic bodies of various shapes and sizes, inparticular, ceramic bodies forming a large structural member or acomplicated shape member.

Next, with reference to FIG. 9, a manufacturing method of a ceramiccomposite member according to the embodiment will be described. FIG. 9is a cross-sectional view illustrating a manufacturing method of aceramic joined member to which the manufacturing method is applied. Notethat a manufacturing method of a ceramic repaired member to which themanufacturing method is applied is implemented by applying the sameprocesses as the manufacturing method of the joined member except thatthe mixture (viscous material) of the first component and the secondcomponent of the ceramic joining material is disposed on a repairposition of a ceramic body. Here, mainly the manufacturing method of thejoined member will be described.

FIG. 9 illustrates manufacturing processes of the ceramic joined memberaccording to the embodiment. First, as illustrated in FIG. 9 (a), afirst and a second ceramic body 51, 52 are prepared as members to bejoined (base members). Here, although steps to join the two ceramicbodies 51, 52 are described, there may be three or more ceramic bodiesas members to be joined (base members). When this embodiment is appliedto the manufacturing method of the ceramic repaired member, a ceramicbody which needs repair (basically one ceramic body) is prepared.

It is preferred that the first and second ceramic bodies 51, 52 bemolded bodies or sintered bodies of silicide ceramics such as siliconcarbides, silicon nitrides, and complex chemical compounds mainlycontaining them or carbide ceramics such as graphite as described above.It is preferred that the first and second ceramic bodies 51, 52 be atleast one selected from a silicon carbide-carbon composite molded body,a silicon carbide-silicon composite sintered body, a silicon carbidesintered body, a silicon nitride sintered body, and graphite. The firstand second ceramic bodies 51, 52 may either be the same kinds of ceramicbodies or different kinds of ceramic bodies. One of the first and secondceramic bodies 51, 52 may be a molded body and the other may be asintered body.

A joining process of this embodiment is particularly preferable forjoining silicon carbide-carbon composite molded bodies together, joiningsilicon carbide-silicon composite sintered bodies together, and joiningsilicon carbide sintered bodies together, and can obtain better resultsin such cases (results of improvement in joining strength, strength in aceramic joined member (composite member) including a joining part, andthe like). This is the same when applying this embodiment to themanufacturing method of the ceramic repaired member, and better resultscan be obtained when it is applied to repair of a siliconcarbide-silicon composite sintered body or a silicon carbide sinteredbody.

Examples of the silicon carbide sintered body forming the ceramic bodies51, 52 include a pressure sintered body and a liquid phase sintered bodyof an ordinary silicon carbide powder, a reaction sintered body of a rawmaterial powder containing a carbon powder (for example, a mixed powderof a carbon powder and a silicon carbide powder), and the like. Thesilicon carbide-carbon composite molded body as the ceramic bodies 51,52 is a green compact of a mixed powder of a silicon carbide powder anda carbon powder, and impregnating this with molten silicon results inthe silicon carbide-silicon composite sintered body.

The silicon carbide-carbon composite molded body is produced by, forexample, applying pressure formation such as powder pressure molding orpressure casting to a mixed powder of a silicon carbide powder and acarbon powder. For the pressure molding of the mixed powder, metallicmold pressing, rubber pressing, cold isostatic pressing, or the like isapplied. When the pressure casting is applied, slurry is prepared bydispersing the mixed powder in water or organic solvent, and pressurecasting this slurry under an appropriate pressure. By applying suchpressure formation, a molded body having a moderate density (fillingstate of powder) can be obtained.

As illustrated in FIG. 9A, a viscous material 53 is disposed between thefirst and second ceramic bodies 51, 52. The viscous material 53 isprepared by mixing a first component formed of a mixture containing asilicon carbide powder, a carbon powder, and a room temperature settingresin, and a second component formed of a curing agent which cures thefirst component (mixture), and has a silicon carbide powder 54, a carbonpowder 55, and a room temperature setting resin composition (mixture ofa base resin and a curing agent) 56. The room temperature setting resinin the viscous material 53 is cured under room temperature, and a shapedproduct 57 having a desired joined member shape is shaped. The viscousmaterial 53 becomes a solidified body adhering to joining faces of thefirst and second ceramic bodies 51, 52 based on the cured product of theroom temperature setting resin cured in the shaping process of theshaped product 57.

Thus, since the viscous material 53 can be solidified under roomtemperature, it is possible to easily and precisely obtain the shapedproduct 57 in which the first ceramic body 51 and the second ceramicbody 52 are joined via the solidified body of the viscous material 53,without fixing the members to be joined with a jig or the like. Further,it is not necessary to fix the shaped product 57 with a jig or the likein a heat treatment process or an impregnation process of molten siliconthereafter, and thus restrictions on shapes, sizes, and the like of theceramic bodies 51, 52 and the joined member can be alleviated. That is,it is possible to join the ceramic bodies 51, 52 of various shapes andsizes by the solidified body of the viscous material 53.

Further, since the viscous material 53 can become a solidified bodyunder room temperature, it is possible to precisely control, forexample, the distance (joining distance) between the first and secondceramic bodies 51, 52 as well as the thickness of the joining part basedon the solidified body of the viscous material 53. The joining distanceis based on the thickness of the joining layer (the solidified bodylayer of the viscous material 53), and further corresponds to thethickness of the joining layer (layer formed of a SiC—Si composite body)after impregnation with molten silicon. The thickness of the joiningpart (joining layer) affects the strength property and the like of thejoined member formed by joining the first ceramic body 51 and the secondceramic body 52. In other words, by precisely controlling the thicknessof the joining part, it is possible to increase strength of the joinedmember and reproducibility thereof.

Next, as illustrated in FIG. 9B, heat treatment is performed on theshaped product 57 to carbonize the cured product of the room temperaturesetting resin. The cured product of the room temperature setting resinis disintegrated by the heat treatment and becomes a carbon porous body58, and this porous body 58 is in a state that the silicon carbidepowder 54 and the carbon powder 55 are dispersed inside. Based on suchheat treatment (carbonization treatment), the solidified body of theviscous material 53 is turned into a porous body 59. It is preferredthat the heat treatment for carbonizing the cured product of the roomtemperature setting resin be performed at temperatures in the range of400° C. to 1300° C. When the heat treatment is performed in a reducedpressure atmosphere, it is preferred to be 1 Pa or lower. By performingthe heat treatment process under such conditions, formability of theporous body 59 improves.

Thereafter, as illustrated in FIG. 9C, the porous body 59 is impregnatedwith molten silicon to produce a ceramic joined member 61, in which thefirst and second ceramic bodies 51, 52 are joined via the joining partformed of a SiC—Si composite body 60. The impregnation process of moltensilicon is performed by heating the shaped product 57 having the porousbody 59 to temperatures in the range of 1400° C. to 1500° C. in areduced pressure atmosphere, and impregnating (vacuum impregnating) theporous body 59 in a heated state with molten silicon under the reducedpressure atmosphere. It is preferred that the reduced pressureatmosphere during the vacuum impregnation is at 1 Pa or lower.

When producing the ceramic repaired member, the viscous material(mixture of the first component and the second component) is applied toa repair position, for example a position where a chip or a crackoccurred, of a ceramic body formed of a silicon carbide-siliconcomposite sintered body, a silicon carbide sintered body, or the like,and the material is shaped. When the repair position has a depth, theviscous material is filled in this portion. Thereafter, the ceramic bodyto which the viscous material is applied is subjected to theabove-described heat treatment process (carbonization process) and theimpregnation process of molten silicon, to thereby produce the ceramicrepaired member having a desired shape.

In the silicon carbide powder 54 existing in the solidified body of theviscous material 53 made to be porous (porous body 59), particles barelygrow during the impregnation process of molten silicon and hence becomefirst SiC particles 62 having a particle diameter substantially equal tothe mean particle diameter of the silicon carbide powder 54. The carboncomponent in the porous body 59, that is, carbon 58 originating from thecarbon powder 55 and the room temperature setting resin composition 56contacts and reacts with the molten silicon under high temperatures andgenerates a silicon carbide (second SiC particles 63). Further, in theporous body 59, the molten silicon remains partially, and this moltensilicon exists as a Si phase 64 in interstices among the first andsecond SiC particles 62, 63.

When the ceramic bodies 51, 52 are silicon carbide-carbon compositemolded bodies or the like, the two molded bodies are impregnated withmolten silicon at the same time as the porous body 59. In theimpregnation process of molten silicon, the two silicon carbide-carboncomposite molded bodies react with the molten silicon and become siliconcarbide-silicon composite sintered bodies. That is, the ceramic joinedmember 61 is produced in which the two silicon carbide-silicon compositesintered bodies, which are reaction sintered in the impregnation processof molten silicon, are integrated by the joining part formed of theSiC—Si composite body 60 formed by allowing reaction simultaneously withthem. The silicon carbide-silicon composite sintered body has astructure similar to the SiC—Si composite body 60 as the joining part.

The joining part formed of the SiC—Si composite body 60 includes thefirst and second SiC particles 62, 63 and the Si phase 64 which existscontinuously in a network form in interstices among the particles. Thatis, the joining part has a dense structure in which interstices amongthe SiC particles 62, 63 are filled with the Si phase 64. When therepair part is formed of the SiC—Si composite body, it has a similarstructure. The second SiC particles 63 based on reaction between acarbon component and molten silicon have a mean particle diametersmaller than that of the first SiC particles 62 based on the siliconcarbide powder 54 blended in the viscous material 53. Based on the meanparticle diameters of the silicon carbide powder 54 and the carbonpowder 55 and the mean particle diameters of the first and second SiCparticles 62, 63 based thereon, the SiC—Si composite body 60 having auniform composite structure (in which the Si phase 64 with a uniformsize exists continuously in interstices among the SiC particles 62, 63)is obtained.

Further, the SiC—Si composite body 60 has the first SiC particles 62 ofappropriate amount based on a blending amount (18% to 60% by volumeratio) with respect to the total powder component of the silicon carbidepowder 54 in the viscous material 53, that is, the first SiC particles62 having a relatively large mean particle diameter. Based on thecontent of the first SiC particles 62 and the mean particle diameter ofthe SiC particles 62 or the like based on the mean particle diameter ofthe silicon carbide powder 54, the distribution states of the second SiCparticles 63 in the SiC—Si composite body 60 and the Si phase 64 areuniformed, and moreover, denseness of the SiC—Si composite body 60 alsoimproves. Also from these, it is possible to increase the strength andreproducibility of the SiC—Si composite body 60.

In the SiC—Si composite body 60, it is preferred that the Si phase 64not only fill the interstices among the SiC particles 62, 63 but existcontinuously in a network form in the interstices among the SiCparticles 62, 63. When the mesh structure of the Si phase 64 is divided,it leads to occurrence of chalking phenomenon (supply route of moltensilicon is interrupted and reaction of carbon stops), and the residualcarbon amount increases, where there is a concern that the strength ofthe joining part formed of the SiC—Si composite body 60 decreases. Inother words, it is possible to obtain a dense and strong joining part byallowing the Si phase 64 to exist continuously in interstices among theSiC particles 62, 63.

In the above-described manufacturing process of the ceramic joinedmember (composite member), it is preferred that the porous body 59 havea mean pore diameter in the range of 0.5 μm to 5 μm. The mean porediameter of the porous body 59 indicates a mean value of diametersobtained using a mercury intrusion method by assuming that they arecolumns. By impregnating the porous body 59 having such a mean porediameter with molten silicon, it is possible to improve strengthproperties (joining strength of the SiC—Si composite body 60, strengthof the SiC—Si composite body 60 itself, strength of the joined member 61including the SiC—Si composite body 60, and so on) based on thedistribution state, the mean diameter, and the like of the Si phase(free Si phase) 64 in the SiC—Si composite body 60.

When the mean pore diameter of the porous body 59 is smaller than 0.5μm, the supply route of the molten silicon is interrupted which can leadto increase in residual carbon amount, and a crack can easily occur dueto volume expansion when a silicon carbide is generated from carbon.When the mean pore diameter of the porous body 59 is larger than 5 theamount of the Si phase 64 increases. Any of these decreases the strengthof the SiC—Si composite body 60. Further, when the mean pore diameter ofthe porous body 59 is too large, a crack or the like can easily occurbefore impregnation with molten silicon, and manufacturing yields andstrength of the ceramic joined member 61 decrease.

Further, it is preferred that the Si phase 54 has a mean diameter in therange of 0.2 μm to 2 μm. The mean diameter of the Si phase 64corresponds to the mean distance among the SiC particles 62, 63. Themean diameter of the SiC phase 64 indicates a value obtained as follows.First, the ceramic joined member 61 having the SiC—Si composite body 60is heated to 1600° C. under a reduced pressure to remove free Si in theSiC—Si composite body 60. The mean diameter of the Si phase 64 indicatesa mean value of diameters obtained by assuming the diameters of smallholes formed by removing free Si as columns using a mercury intrusionmethod. This value matches results of cross-section observation of theminute structure of SiC—Si composite body 60 with a metallurgicalmicroscope or SEM.

When the mean diameter of the Si phase 64 is small, this means that theSi phase 64 with low strength is miniaturized. Further, this also meansthat the Si phase 64 is distributed homogeneously in interstices amongthe SiC particles 62, 63. The interstices among the SiC particles 62, 63are filled evenly with the Si phase 64. By thus controlling the meandiameter of the Si phase 64 to be in the range of 0.2 μm to 2 μm,strength of the joining part formed of the SiC—Si composite body 60 andfurther strength as the ceramic joined member 61 including the joiningpart can be increased with good reproducibility.

When the mean diameter of the Si phase 64 is larger than 2 μm, itbecomes close to a state that the Si phase 64 with low strength issegregated, and the influence of the Si phase 64 on strength of theSiC—Si composite body 60 becomes large. Therefore, strength of theSiC—Si composite body 60 and strength of the ceramic joined member 61decrease easily. When the mean diameter of the Si phase 64 is smallerthan 0.2 μm, it is difficult to maintain the continuous structure in anetwork form. Accordingly, pores or free carbon can occur easily in theSiC—Si composite body 60, and dispersion in strength of the joining partcan easily occur. This is similar when a repair part is formed of aSiC—Si composite body.

The mean diameter of the Si phase 64 can be controlled based on the meanpore diameter of the porous body 59 before impregnation with moltensilicon and the mean particle diameters of the silicon carbide powder 54and the carbon powder 55 blended in the viscous material 53. That is, byusing the silicon carbide powder 54 having a mean particle diameter inthe range of 0.5 μm to 5 μm and the carbon powder 55 having a meanparticle diameter in the range of 0.3 μm to 3 and controlling the meanpore diameter of the porous body 59 to be in the range of 0.5 μm to 5μm, the Si phase 64 which is minute and homogeneous (for example, the Siphase 64 with a mean diameter in the range of 0.2 μm to 2 μm) can beobtained.

In the manufacturing process of the ceramic composite member, it ispreferred that the impregnation process of molten silicon be performedat temperatures in the range of 1400° C. to 1500° C. It is preferredthat the reduced pressure atmosphere for impregnating molten silicon isat 1 Pa or lower. By performing the impregnation process of moltensilicon under such conditions, an impregnation characteristic of moltensilicon and formability of the SiC particles 63 improve, and minutepores (micro-pores or nano-pores) in the Si phase 64 can be decreasedsignificantly. Therefore, strength of the SiC—Si composite body 60 andreproducibility thereof can be increased.

In the manufacturing process of the ceramic joined member 61 in thisembodiment, when two ceramic bodies 51, 52 are joined with the viscousmaterial 53, they can be cured in a state that the joining part isshaped in a predetermined form. Thus, it is applicable to a largestructural member, a complicated shape part, and the like and theprecision of shape of the joining part can be increased. Therefore, itis possible to obtain a joining part in which dispersion in strength andmaterial properties such as thermal properties are suppressed.

With the above-described joining part, in addition to improvement in itsmaterial properties, it is possible to improve material properties ofthe ceramic joined member 61 having the joining part and reproducibilitythereof. Since it is unnecessary to fix members to be joined with a jigor the like, manufacturing costs and the number of manufacturing stepsof the ceramic joined member 61 can be reduced. Note that it is notintended to prohibit use of a jig or the like when the shapes of joinedmembers are complicated or when there are many joining positions.

Further, in the manufacturing process of the ceramic joined member 61,the joining part formed of the SiC—Si composite body 60 excels not onlyin joining strength with respect to the ceramic bodies 51, 52 but in itsstrength and reproducibility thereof. Therefore, a plurality of ceramicbodies 51, 52 can be joined with high strength, and strength of theceramic joined member 61 can be increased with good reproducibility.These make it possible to provide the ceramic joined member 61 with highstrength at low cost, which is preferable for complicated shapes andlarge structural members and parts. Further, this is also the same whenthe manufacturing process of this embodiment is applied to production ofa ceramic repaired member, and increase in strength of ceramic repairedmembers, improvement in precision of shape, cost reduction, and so oncan be achieved.

In the above-described composite members such as the ceramic joinedmember 61 and the ceramic repaired members, mechanical properties suchas strength can be increased with good reproducibility, and thus theyare applicable to various members and parts which are required to havehigh strength. They contribute largely to increase in strength inparticular of large structural objects, complicated shape parts, and thelike. The ceramic composite member can be applied to various apparatusparts and apparatus members such as semiconductor manufacturingapparatus jigs, semiconductor related parts (heat sinks, dummy wafers,and the like), high-temperature structural members for gas turbine,high-temperature members for heat accumulator, structural members forspace and aerial use, mechanical sealing members, brake members, slidingparts, mirror parts, pump parts, heat exchanger parts, chemical plantcomponents, and the like. In particular, the ceramic composite member isused preferably for apparatus parts and members which are required tohave high strength.

Next, specific examples and evaluation results thereof will bedescribed.

(Viscous Materials 1 to 6)

Viscous materials 1 to 6 were produced as follows. First, as the roomtemperature setting resin composition, an epoxy-based resin compositionand a phenol-based resin composition which have a room temperaturesetting property were prepared. To the base resin of each roomtemperature setting resin composition illustrated in Table 1, a siliconcarbide powder having a mean particle diameter in the range of 0.5 μm to5 μm and a carbon powder having a mean particle diameter in the range of0.3 μm to 3 μm were added and mixed. The mean particle diameters of thesilicon carbide powder and the carbon powder, the volume ratio of thesilicon carbide powder in the viscous material, and the total mass ratioof the silicon carbide powder and the carbon powder are as illustratedin Table 1.

To each mixture of the above-described base resin of the roomtemperature setting resin composition, the silicon carbide powder, andthe carbon powder, the curing agent of the room temperature settingresin composition was added and mixed sufficiently, thereby preparingviscous materials 1 to 6. Note that the curing agent of the roomtemperature setting resin composition was mixed just before the viscousmaterial is applied in the manufacturing process of the ceramiccomposite member (for joined members, just before disposing betweenjoining faces of the ceramic bodies, and for repaired members, justbefore disposing on a part of a ceramic body) of examples 1 to 15, whichwill be described later. Specific structures of the viscous materials 1to 6 are as illustrated in Table 1.

TABLE 1 Powder component Silicon carbide Carbon powder powder Resincomponent Mean Mean Total (room particle Volume particle masstemperature diameter ratio diameter ratio setting resin) (μm) (%) (μm)(%) Viscous Epoxy resin 0.5 18 0.3 29 material 1 Viscous Epoxy resin 122 1 44 material 2 Viscous Epoxy resin 2 40 1 47 material 3 ViscousPhenol resin 1 27 0.8 33 material 4 Viscous Phenol resin 2 45 1.5 47material 5 Viscous Phenol resin 5 60 3 55 material 6

Example 1

The silicon carbide powder having a mean particle diameter of 0.8 μm andthe carbon powder (carbon black) having a mean particle diameter of 0.4μm were mixed with a mass ratio of 10:3 (═SiC:C). After this mixedpowder was mixed with an appropriate amount of organic binder andthereafter it was dispersed in a solvent, thereby preparing slurry. Thisslurry was filled into a forming die using a pressure casting devicewhile applying a pressure. In this manner, two SiC—C composite moldedbodies (green compacts) were produced.

Next, after the viscous material 1 in Table 1 was disposed betweenjoining faces of the two SiC—C composite molded bodies, the roomtemperature setting resin composition was cured to make a shaped producthaving a desired joined member shape. This shaped product was heated toa temperature of 1000° C. in a nitrogen or argon atmosphere, so as tocarbonize the cured product of the room temperature setting resincomposition. In this carbonization treatment, the solidified body of theviscous material becomes a porous body. The mean pore diameter of theporous body was 1.0 μm. Thereafter, the shaped product in which the twomolded bodies are connected by the porous body was heated to atemperature of 1450° C. in a reduced pressure atmosphere at 1 Pa orlower, and meanwhile the two molded bodies and the porous body formingthe joining part were impregnated with molten silicon.

Next, in the impregnation process of molten silicon, the two moldedbodies were made to react with molten silicon, so as to make SiC—Sicomposite sintered bodies, and they were joined with the SiC—Sicomposite body which is a product of reaction of the porous body and themolten silicon. Regarding the ceramic joined member obtained in thismanner, after the surface of the joining part formed of the SiC—Sicomposite body was polished, the minute structure was observed with anelectron microscope. As a result, it was recognized that the joiningpart has a structure in which the Si phase exists continuously in anetwork form in interstices among the SiC particles. The mean diameterof the Si phase was 0.7 μm. Such a ceramic composite member wassubjected to property evaluation, which will be described later.

Example 2

Two SiC—C composite molded bodies produced similarly to example 1 wereheated to a temperature of 600° C. and held in an inert as atmosphere,so as to remove the organic binder. The molded body after beingdegreased was heated to a temperature of 1450° C. in a reduced pressureatmosphere at 1×10⁻¹ Pa, and the molded body keeping this heated statewas impregnated with molten silicon. By causing reaction sintering ofthe molded body in the impregnation process of molten silicon(generation of SiC and densification by the Si phase), two SiC—Sicomposite sintered bodies were produced.

Next, after the viscous material 2 in Table 1 was disposed betweenjoining faces of the two SiC—Si composite sintered bodies, the roomtemperature setting resin composition was cured to make a shaped producthaving a desired joined member shape. This shaped product was heated toa temperature of 800° C. in an inert atmosphere, so as to carbonize thecured product of the room temperature setting resin composition. In thiscarbonization treatment, the solidified body of the viscous materialbecomes a porous body. The mean pore diameter of the porous body was 0.8μm. Thereafter, the shaped product in which the two sintered bodies areconnected by the porous body was heated to temperatures of 1400° C. to1500° C. in a reduced pressure atmosphere at 1 Pa or lower, andmeanwhile the porous body forming the joining part were impregnated withmolten silicon.

Next, in the impregnation process of molten silicon, the two SiC—Sicomposite sintered bodies were joined with the SiC—Si composite bodywhich is a product of reaction of the porous body and the moltensilicon. Regarding the ceramic joined member obtained in this manner,after the surface of the joining part formed of the SiC—Si compositebody was polished, the minute structure was observed with an electronmicroscope. As a result, it was recognized that the joining part has astructure in which the Si phase exists continuously in a network form ininterstices among the SiC particles. The mean diameter of the Si phasewas 0.5 μm. Such a ceramic composite member was subjected to propertyevaluation, which will be described later.

Examples 3 to 10

As members to be joined, there were prepared SiC—C composite moldedbodies, SiC—Si composite sintered bodies, SiC sintered bodies by powdersintering method, and Si₃N₄ sintered bodies. They were joined based oncombinations illustrated in Table 2 to produce ceramic joined members.The joining process was performed similarly to examples 1, 2. Viscousmaterials used for joining are as illustrated in Table 2. Table 3illustrates structures of joining parts. All the joining parts of therespective ceramic joined members had a structure in which a Si phaseexists continuously in a network form in interstices among SiCparticles. Each of the ceramic joined members was subjected to propertyevaluation, which will be described later.

Comparative Example 1

A silicon foil was sandwiched between two SiC—Si composite sinteredbodies produced similarly to example 2, and they were fixed by a jig.Thereafter, they were heated to temperatures at which the silicon foilmelts, so as to join them. A ceramic joined member obtained in thismanner was subjected to property evaluation, which will be describedlater.

Comparative Example 2

On joining faces of two SiC—Si composite molded bodies producedsimilarly to example 1, slurry prepared by dispersing a silicon carbidepowder, a carbon powder, and the like in a solvent was applied to jointhem, and they were fixed with a jig. Thereafter, they were impregnatedwith molten silicon similarly to example 1. A ceramic joined memberobtained in this manner was subjected to property evaluation, which willbe described later.

TABLE 2 Joining Ceramic body 1 Ceramic body 2 material Example 1 SiC—Ccomposite SiC—C composite Viscous molded body molded body material 1Example 2 SiC—Si composite SiC—Si composite Viscous sintered bodysintered body material 2 Example 3 SiC—C composite SiC—C compositeViscous molded body molded body material 3 Example 4 SiC—C compositeSiC—C composite Viscous molded body molded body material 4 Example 5 SiCsintered body SiC sintered body Viscous material 5 Example 6 Sicsintered body SiC sintered body Viscous material 6 Example 7 SiC—Sicomposite SiC sintered body Viscous sintered body material 2 Example 8SiC—C composite SiC—Si composite Viscous molded body sintered bodymaterial 3 Example 9 Si₃N₄ sintered body Si₃N₄ sintered Viscous bodymaterial 4 Example 10 Si₃N₄ sintered body Si₃N₄ sintered Viscous bodymaterial 5 Comparative SiC—Si composite SiC—Si composite Silicon foilExample 1 sintered body sintered body Comparative SiC—C composite SiC—Ccomposite Slurry Example 2 molded body molded body

Measurement of joining strength (4-point bending measurement) of therespective ceramic joined members according to examples 1 to 10 andComparative Examples 1 and 2 was conducted in accordance with JIS R1624. Results are illustrated in Table 3. Table 3 illustrates mean porediameters of porous bodies formed in the course of manufacturing theceramic joined members, as well as mean diameters of Si phases in thefinal ceramic joined members. Further, applicable ranges ofmanufacturing processes of the examples are studied. One applicable to alarge structural member, a complicated shape part, or the like is marked“Yes”, and one which is practically difficult to apply is marked “No”.

TABLE 3 Joining part Mean pore Mean Bending diameter (μm) of diameter ofstrength Applicable porous layer Si phase (μm) (MPa) range Example 1 1.00.7 600-650 Yes Example 2 0.8 0.5 700-750 Yes Example 3 0.5 0.2 850-900Yes Example 4 1.5 0.9 550-600 Yes Example 5 2.5 1.5 400-450 Yes Example6 4.0 2.5 350-400 Yes Example 7 2.0 1.2 600-700 Yes Example 8 0.7 0.4750-800 Yes Example 9 3.0 1.8 400-450 Yes Example 10 0.9 0.6 650-700 YesComparative — — 80 No Example 1 Comparative — 10 100 No Example 2

As is clear from Table 3, it can be seen that the ceramic joined membersof examples 1 to 10 all excel in mechanical properties such as joiningstrength, as compared to Comparative Examples 1 and 2. It was recognizedthat the joining part has properties equivalent to those of the SiC—Sicomposite sintered body or the like of the base member. Further, it wasrecognized that the joining parts according to examples 1 to 10 alsoexcel in thermal properties such as heat conductivity. Note that theheat conductivity was measured in accordance with JIS R 1611. Further,examples 1 to 10 can be applied to members and parts of various shapesand sizes. Regarding the sizes, it was recognized that they areapplicable to large structural members of meter-class size.

In Comparative Example 1, the members must be fixed with a jig or thelike so as to keep the joined shape and prevent the sandwiched siliconfoil from falling off while being heated. Further, heating must beperformed in a state that melted silicon would not drip off.Accordingly, application to parts of various shapes and sizes,particularly to large structural members and complicated shape parts isdifficult. In a state of being joined with the slurry of ComparativeExample 2 and dried, members have almost no strength, and thusapplication of the manufacturing process of Comparative Example 2 toparts of various shapes and sizes, particularly to large structuralmembers and complicated shape parts is difficult.

Example 11

A SiC—Si composite sintered body was produced similarly to example 2,and a cutout was formed thereon for forming a repair part. The size ofthe cutout was 20 mm. In the cutout of this SiC—Si composite sinteredbody, the viscous material 2 of Table 1 was applied and filled, andthereafter the room temperature setting resin composition was cured.This SiC—Si complex sintered body was heated to a temperature of 1000°C. in an inert atmosphere to carbonize the cured product of the roomtemperature setting resin composition. The solidified body of theviscous material becomes a porous body through this carbonizationtreatment. The mean pore diameter of the porous body was 0.5 μm to 2.0μm. Thereafter, the SiC—Si composite sintered body was heated to atemperature of 1450° C. in a reduced pressure atmosphere at 1 Pa orlower, and meanwhile the porous body forming the repair part wasimpregnated with molten silicon.

In the impregnation process of molten silicon, the cutout of the SiC—Sicomposite sintered body was repaired with the SiC—Si composite bodywhich is the product of reaction between the porous body and the moltensilicon. Regarding the ceramic repaired member obtained in this manner,after the surface of the repair part formed of the SiC—Si composite bodywas polished, the minute structure was observed with an electronmicroscope. As a result, it was recognized that the repair part has astructure in which the Si phase exists continuously in a network form ininterstices among the SiC particles. The mean diameter of the Si phasewas 0.2 μm to 1.2 μm. Strength of this ceramic repaired member wasmeasured, and it was recognized that it has strength equivalent to thatof a SiC—Si composite sintered body which does not have a repair part.

Examples 12 to 15

As members to be repaired, there were prepared a SiC—Si compositesintered body, a SiC—Si composite molded body, and SiC sintered bodiesby powder sintering method. They were repaired based on combinationsillustrated in Table 4 to produce ceramic repaired members. Therepairing process was performed similarly to example 11. Viscousmaterials used for repair are as illustrated in Table 4. Results ofmeasuring strength of each ceramic repaired member are illustrated inTable 5. Table 5 also illustrates structures of the repair parts.

TABLE 4 Ceramic body Repair material Example 11 SiC—Si composite Viscousmaterial 2 sintered body Example 12 SiC sintered body Viscous material 2Example 13 SiC—C composite Viscous material 2 molded body Example 14SiC—Si composite Viscous material 5 sintered body Example 15 SiCsintered body Viscous material 5

TABLE 5 Repair part Mean pore Mean diameter diameter (μm) of of Si phaseBending porous layer (μm) strength (MPa) Example 11 0.5-2.0 0.2-1.2600-900 Example 12 1.0-4.0 0.6-2.5 350-600 Example 13 0.5-2.0 0.2-1.2600-900 Example 14 0.8-1.5 0.5-0.9 550-750 Example 15 2.0-5.0 1.2-2.0350-600

As is clear from Table 5, all the ceramic repaired members in whichrepair parts are formed with a SiC—Si composite body have strengthequivalent to that of a sintered body having no repair part, andeffectiveness of the repair parts formed of a SiC—Si composite body wasrecognized. Further, the viscous materials used as a repairing materialcan be solidified during molding, and thus it is possible to increasethe shape precision of a repair part. Therefore, reliability and repairyields of repaired ceramic members improve.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the inventions. Indeed, the novel embodiments described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of theinventions. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the inventions.

What is claimed is:
 1. A manufacturing method of a ceramic compositemember, comprising: mixing a silicon carbide powder having a meanparticle diameter in a range of 0.5 μm to 5 μm and a carbon powderhaving a mean particle diameter in a range of 0.3 μm to 3 μm with a roomtemperature setting resin having viscosity and adhesiveness to obtain afirst mixture containing the silicon carbide powder, the carbon powder,and the room temperature setting resin, wherein the room temperaturesetting resin comprises a phenol resin having a room temperature settingproperty as a primary component of the room temperature setting resin;mixing a curing agent of the room temperature setting resin which curesthe first mixture with the first mixture to obtain a viscous material asa second mixture, wherein a total mass percentage of the silicon carbidepowder and the carbon powder in the viscous material is from 29% to 55%,and a volume percentage of the silicon carbide powder to all the powdercomponents in the viscous material is from 18% to 60%; disposing theviscous material between a plurality of ceramic bodies or on a part of aceramic body; curing the room temperature setting resin under a roomtemperature to solidify the viscous material adhered to the ceramicbodies or the ceramic body, and making a shaped product having asolidified body of the viscous material; heat treating the shapedproduct at a temperature of from 800° C. to 1000° C. to carbonize acured product of the room temperature setting resin, so as to cause thesolidified body of the viscous material to be porous; and producing aceramic composite member having a silicon carbide-silicon composite bodyformed by impregnating at least the porous solidified body of theviscous material with molten silicon, causing carbon components in thesolidified body to react with the molten silicon, and leaving part ofthe molten silicon as a silicon phase, wherein the siliconcarbide-silicon composite body as a joining part or a repair partcomprises silicon carbide particles based on the silicon carbide powderand reactants of the carbon components and the molten silicon, and thesilicon phase existing continuously in interstices among the siliconcarbide particles.
 2. The manufacturing method of the ceramic compositemember according to claim 1, wherein the silicon carbide particlescomprises first silicon carbide particles based on the silicon carbidepowder and second silicon carbide particles generated by reactionbetween the carbon components and the molten silicon.
 3. Themanufacturing method of the ceramic composite member according to claim1, wherein the plurality of ceramic bodies are joined via the siliconcarbide-silicon composite body, and wherein each of the ceramic bodiesis formed of a silicon carbide-carbon composite molded body, a siliconcarbide-silicon composite sintered body, a silicon carbide sinteredbody, a silicon nitride sintered body, or graphite.
 4. The manufacturingmethod of the ceramic composite member according to claim 1, wherein thepart of the ceramic body is repaired with the silicon carbide-siliconcomposite body, and wherein the ceramic body is formed of a siliconcarbide-carbon composite molded body, a silicon carbide-siliconcomposite sintered body, a silicon carbide sintered body, a siliconnitride sintered body, or graphite.
 5. The manufacturing method of theceramic composite member according to claim 1, wherein a mean porediameter of the porous solidified body is in the range of 0.5 μm to 5μm.
 6. The manufacturing method of the ceramic composite memberaccording to claim 1, wherein a mean diameter of the silicon phase inthe silicon carbide-silicon composite body is in the range of 0.2 μm to2 μm.
 7. The manufacturing method of the ceramic composite memberaccording to claim 1, wherein the viscous material only contains theroom temperature setting resin as a resin component.